When working on your car, it’s important to know how to turn the crankshaft. This tutorial will show you how. I’ve also advised you what to do while turning the crankshaft and made suggestions in case you struggle to turn the crankshaft.
The main tool you need is a long breaker bar (½” should do), plus a socket that fits the crankshaft bolt. Among other measures, disable the ignition system, remove the spark plugs, and put the car into the neutral gear, but keep the timing belt on. Then apply these four steps: wedge the breaker in the control arm put the socket on the bolt, turn the harmonic balancer as necessary, and push to start turning the bar clockwise.
Why You Would Need to Do It
The crankshaft drives various parts outside the engine casing.
You might need to turn a crankshaft if, for instance, you think the engine is seized. If you think this is the case, remove the spark plugs and try rotating the engine. If you can’t rotate it by hand, it might be seized.
Using a breaker bar can also confirm if it is able to turn or not.
Essential Prerequisites
The Tools to Use
Make sure you have the right breaker bar. It must be one with a long handle.
A ratcheting breaker bar will help to keep turning the crankshaft in the right direction. You may need a long ½” bar. Although many suggest it, avoid using a torque wrench, as it can get damaged easily. A breaker bar is a right tool for this job.
To loosen the crankshaft bolt, you will probably need a 14mm socket. Check the required size and use the right socket that fits.
Safety and Other Measures
Before starting to turn the crankshaft, take the following main safety and other measures:
- Disable the ignition system or remove the starter because you don’t want the engine accidentally starting while turning the crankshaft.
- Remove the spark plugs to make the task easier. Removing them releases pressure inside the engine that could otherwise hinder your effort.
- Put the car into neutral gear.
- Keep the timing belt on, i.e., don’t remove it because most engines don’t turn easily if the timing belt is not present. Also, keep the battery connected.
- Make sure no one else is near the breaker bar to prevent them from getting hurt.
Know the Direction to Turn
The direction you likely want to turn the crankshaft will be clockwise, as it is the direction in which the engine turns freely. It is clockwise if looking at the crankshaft pulley from the driver-side fender well.
The Steps to Take
After following the essential prerequisites mentioned above, proceed as suggested below.
- Securely wedge the breaker bar in the control arm.
- Put the socket on the crankshaft bolt.
- Turn the round harmonic balancer or pulley at the front of the engine (which drives the belt) until you can easily attach the bar to the socket without obstruction.
- Turn the bar clockwise.
While Turning the Crankshaft
While turning the crankshaft, don’t give up easily if you find it difficult.
Obviously, you will feel resistance, but keep trying and exerting effort steadily. Don’t worry about breaking anything, as the risks are low. Sooner or later, you will notice the resistance subsiding, as soon as you hear a click or two, or notice a slight release of air.
After a few revolutions, you will be able to continue turning the crankshaft with greater ease compared to the initial struggle.
Extra Things to Try
If the crankshaft still fails to turn, try one or more of the following:
- Try using a longer breaker bar, if available, or else add a long pipe over the bar.
- Try to avoid doing this, but if necessary, remove the timing belt, as it might help a little, but also the rocker arms to avoid timing issues later.
- Check if any other rotating component in the assembly is preventing the crankshaft from turning.
- If it feels like it is jammed, try turning it the other way only a little before resuming to turn it in the required direction.
- Remove the spark plugs; if you haven’t done so already, spray the PB blaster down each cylinder to loosen the rings in case they are bound up. You can use motor oil as an alternative. Let it soak through to the spark plug wells first before trying again.
- Have someone step on the clutch while trying again.
- Rock the car gently to help rotate the engine.